1. Field of the Invention
The present invention relates to a magnifying observation apparatus such as a digital microscope or a microscope which captures and displays a magnified image, a magnified image observing method, a magnified image observing program, and a computer-readable recording medium.
2. Description of Related Art
As a magnifying observation apparatus that magnifies and displays an image of a subject being a specimen such as a micro-object, a workpiece or the like, there has been used an optical microscope, a digital microscope or the like which uses an optical lens. In the digital microscope, reflected light or transmitted light which is incident via an optical system and comes from an observation target fixed to an observation target fixing section is received with an imaging element such as a CCD or a CMOS where the light is electrically read at each of two-dimensionally arranged pixels, and the electrically read image is displayed on a display section such as a display (e.g., JP 2012-145722 A, JP 2004-170574 A).
Some of such magnifying observation apparatuses are provided with a function (synthetic image mode) of synthesizing an image from a plurality of images. For example, out of a plurality of images photographed as a focus position is changed, only focused portions are synthesized from focus information, to obtain an image with a large depth of focus (synthetic depth image) with respect to an image with a small depth of focus. Further, there is known a technique of acquiring an image with resolution increased by a so-called super-resolution technique, or an image with a widened dynamic range. Since such a synthetic image is generated from a plurality of images, it requires considerably long processing time. For this reason, for generating and displaying the synthetic image, it is difficult to keep displaying on the display section a real time image (a live picture or a moving image) with a high frame rate, and hence the frame rate is significantly lowered or the image is displayed as a still image.
While each of these synthetic images is displayed, a display content on the display section is the still image or is in the state of having an extremely slow frame rate. For this reason, when another portion is to be observed, it is of necessity to once discard the still image and switch the display content on the display section to a through image mode for displaying a live picture. That is, the user has been required to perform an operation of switching display on the display section from the still image to the moving image.
Further, in a state where the live picture is displayed on the display section with the frame rate of the imaging element set to high, a user searches a portion to be observed while referring to the display section, to decide a visual field. Then in a state where the desired portion has been decided, since the live picture remains displayed, synthesis processing needs to be executed again for this portion. That is, it has been necessary to perform an operation of performing switching to the synthetic image mode and change the display content on the display section from the live picture to the still image. As thus described, since an image required at the time of performing the synthesis processing required for observation is different from that required at the time of searching the desired portion, the user is forced to perform an operation of turning on/off the synthetic image mode and switching the display content each time, which has caused a problem of making the operation extremely complicated.